After a horrific attack by a renegade fathers for justice style group Lily Blake manages to escape the fiery death they had planned for her only to discover her children have been kidnapped.
She suspects her ex-husband organised the attack but he has apparently disappeared as well. The police and FBI are unable to track down the kidnappers and in desperation Lily calls on a local Native American who puts her in touch with George Iron Walker who offers her the assistance of a native American spirit, for a price, that being a piece of local ground sacred to his tribe. She is warned that the deal they have made must be met in full or she must face the consequences.
The Wendigo, although a spirit of the woods, is described as a flesh eater who demands a blood sacrifice but it takes a while for her to realise the spirit is on a hunting mission to kill those responsible she desperately tries to back out of the deal.
It's an enjoyable fast paced story, albeit with one "major" flaw as you may realise as you get to the end of the book.
The Wendigo's changing appearance probably, becoming invisible when it turnes side-on "edgewise" owes a lot to the 2001 movie which is mentioned in the text
Wendigo [DVD] [2001], as is the Algernon Blackwood short story which is included in this omnibus,
Best Ghost Stories and certainly not to the Marvel comics character.
Well worth reading and although not the best Graham Masterton book I have read it certainly holds your attention.